In recent years, following the spread of hybrid automobiles, electric automobiles, and the like, high-current connector terminals have been used for, for example, power supply lines for supplying electric power to a motor and the like. Typically, electrical contacts of this type of connector terminal employ Ag plating, which has low contact resistance. When the connector terminals are fitted to each other, the Ag layers of electrical contacts are brought into contact with each other, and a contact portion of a pair of electrical contacts is formed.
For example, Patent Document 1 (JP2013-231228A) discloses, as the above-described connector terminal, a connector terminal that is constituted by a plated member including: a base material made of Cu or a Cu alloy; an Ag—Sn alloy layer that covers a surface of the base material; and an Ag layer that covers the Ag—Sn alloy layer, and is exposed as the outermost surface.